Among the assumptions of the classical economic order quantity (EOQ) model is that all units that are purchased (or produced) are of perfect quality. However, this is frequently unrealistic since production processes deteriorate resulting in the production of defective products requiring rework. Some recent studies suggest that production systems performance might be improved by applying the fi...

In economic order quantity models without backordering, both the stock cost of each unit quantity and the order cost of each cycle are characterized as independent fuzzy variables rather than fuzzy numbers as in previous studies. Based on an expected value criterion or a credibility criterion, a fuzzy expected value model and a fuzzy dependent chance programming (DCP) model are constructed. The...

 This paper presents an inventory model with non-instantaneous receipt under the condition of permissible delay in payments. Certain items like volatiles deteriorate during production process. In this paper, we consider deterioration into two phases i.e. phase 1 and phase 2. The purpose of this paper is to determine the optimal replenishment policies under conditions of non-instantaneous recei...

The items that incur a gradual loss in quality or quantity over time while in inventory are usually called deteriorating items. In reality, there are some items whose value or utility or quantity increase with time and those items can be termed as ameliorating items. In this paper, an effort has been made to incorporate these two opposite physical characteristics of stored items into inventory ...

While deterioration models consider the gradual reduction in quality and quantity of products over time, amelioration models assume the opposite. This paper is based on an earlier work by Hwang for finding an optimal economic order quantity solution for items subject to amelioration in a Weibull distribution. Hwang solved the problem with a graphical procedure. In this paper, a rigorous analyti...

This paper seeks the critical factors for a correct choice in the components set up along the supply chain. ABC classification was made for all the suppliers according to the supplied items for the company. After a demand analysis, the seasonal nature and trend during the timeline, we used the last four years registers where is shown a decreasing behavior in 30% of the items; Economic Order Qua...

This paper studies the economic-order-quantity model (EOQ) for deteriorating items in two cases (with and without shortages) to evaluate how vendor managed inventory (VMI) affects supply chain. We consider two-level supply chain (single supplier and a single retailer) with one instantaneous deteriorating item. A numerical example and sensitivity analysis are provided to illustrate the effect of...

This section is devoted to the Economic Production Quantity (EPQ) model, its specialization to the Economic Order Quantity (EOQ) model and its extension to allow backorders. The next section deals with multiple products. The primary driver to hold inventories is the presence of a fixed production/ordering cost that is incurred every time a positive number of units are produced/ordered. We wish ...

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